//	VirtualDub - Video processing and capture application
//	Copyright (C) 1998-2001 Avery Lee
//
//	This program is free software; you can redistribute it and/or modify
//	it under the terms of the GNU General Public License as published by
//	the Free Software Foundation; either version 2 of the License, or
//	(at your option) any later version.
//
//	This program is distributed in the hope that it will be useful,
//	but WITHOUT ANY WARRANTY; without even the implied warranty of
//	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//	GNU General Public License for more details.
//
//	You should have received a copy of the GNU General Public License
//	along with this program; if not, write to the Free Software
//	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

#include "stdafx.h"

#include "../../filters/misc.h"

extern long CPUCheckForExtensions();  // in cpuaccel.cpp

long __declspec(naked) MulDivTrunc(long a, long b, long c) {
	__asm {
		mov eax,[esp+4]
		imul dword ptr [esp+8]
		idiv dword ptr [esp+12]
		ret
	}
}

unsigned __declspec(naked) __stdcall MulDivUnsigned(unsigned a, unsigned b, unsigned c) {
	__asm {
		mov		eax,[esp+4]
		mov		ecx,[esp+12]
		mul		dword ptr [esp+8]
		shr		ecx,1
		add		eax,ecx
		adc		edx,0
		div		dword ptr [esp+12]
		ret		12
	}
}

int NearestLongValue(long v, const long *array, int array_size) {
	int i;

	for(i=1; i<array_size; i++)
		if (v*2 < array[i-1]+array[i])
			break;

	return i-1;
}

bool isEqualFOURCC(FOURCC fccA, FOURCC fccB) {
	int i;

	for(i=0; i<4; i++) {
		if (tolower((unsigned char)fccA) != tolower((unsigned char)fccB))
			return false;

		fccA>>=8;
		fccB>>=8;
	}

	return true;
}

bool isValidFOURCC(FOURCC fcc) {
	return isprint((unsigned char)(fcc>>24))
		&& isprint((unsigned char)(fcc>>16))
		&& isprint((unsigned char)(fcc>> 8))
		&& isprint((unsigned char)(fcc    ));
}

FOURCC toupperFOURCC(FOURCC fcc) {
	return(toupper((unsigned char)(fcc>>24)) << 24)
		| (toupper((unsigned char)(fcc>>16)) << 16)
		| (toupper((unsigned char)(fcc>> 8)) <<  8)
		| (toupper((unsigned char)(fcc    ))      );
}

#if defined(WIN32) && defined(_M_IX86)

	bool IsMMXState() {
		char	buf[28];
		unsigned short tagword;

		__asm fnstenv buf

		tagword = *(unsigned short *)(buf + 8);

		return (tagword != 0xffff);
	}

	void ClearMMXState() {
		if (CPUCheckForExtensions() & 0x04)     // MMX supported
			__asm emms
		else {
			__asm {
				ffree st(0)
				ffree st(1)
				ffree st(2)
				ffree st(3)
				ffree st(4)
				ffree st(5)
				ffree st(6)
				ffree st(7)
			}
		}
	}

#else

	bool IsMMXState() {
		return false;
	}

	void ClearMMXState() {
	}

#endif
